Track shoe



May 20, 1941- v. o. BEEDE TRACK SHOE Filed oct. 11, 1939 factured and used by or bored to receive transmitting the track -pull Patented May 2 0, 1941 UNITED STATES PATENT OFFICE 2,242,222 'mack snor: v virgin o. Beede, arinztoava. Application october 11,1939. ser-isi No. 298,969

' 1o claims. (ci. 395-19) (Granted under amended April The invention described hereinv may be manui'or the Government for governmental purposes. without the payment to me of any royalty thereon. Y

This invention relates to a track shoe for .tracks employed in vehicles of the tracklaying type.

In the prior art it has been commonplace to utilize a track shoe in the fabrication of tracks.

the act of March 3, 30, 1928; 370 (LG.

which comprises a pair of spaced parallel tubular members joined into a rigid unit by interconnecting side plates and suitably embedded in a resilient tread substance, such as rubber, as exemplified for example by U. S. Patent No. 2,113,018. While this general type of' shoe is desirable in a track'it is nevertheless subject to failure at lthe points where theside links are the tubular members when the tread is sufficiently worn away -to permit contact of the side plates with the ground due to the small sectional area of metal at these points for stress between adjacent tubular v members. Moreover, the side plates preclude the full use of the depth of rubber on the traction face of the shoe as the effective depth of the tread and seriously interfere with the employment of suitable ventilating expedients for keeping the track at a desirable temperature.

-Accordingly it is a principal object of this invention to setfo'rth an economical track shoe oonstruction -wherein side plates have been eliminated.

Fig. 1 is a plan view of a track shoe insert embodying this invention.

Fig. 2 is an end eleva ion of a track shoe embodying the track shoe insert shown in Fig. 1.

Fig. 3 is a cross section of a track shoe similar to the one disclosed in Figs.- 1 and 2 showing a slight modification.

Figs. 4 and 5 are fragmentary sectional views showing modifications, and v Fig. 6 is a modification of the reinforcing\ frame or insert of this invention. f n Referring'now to the drawing of reference and more particularly to Fig. 2 there is shown a trackshoe I0 adapted to be interconnected in spaced relation with similar track shoes to form an endless track. As the means for interconnecting the shoes into an endless track form no part of the present invention and may comprise any of the expedients suitable for such purpose so well known in the art it will suiiice for the purpose of this invention to simply refer to U. S. Patent 2,129,696 which in Figs. 1 and 2 discloses one type .of link means that may be used for such purpose. v

The track shoe I0 is a composite structure comprising the reinforcing frame or insert Il slltably embedded within-an outer resilient block As disclosed .in Fig. 2 the insert ii is comprised of a pair of oppositely disposed spaced parallel rectanglar members I3 and *Il joined to It is another important object of this inven- Itionto provide a track shoe having a resilient ltraction face in which substantially the full depth ofthe resilient substance comprising the face may be effectively utilized as a tread or traction surface.

A still further-object of this invention is the provision ofy a track'shoe having a reslient'tread surface formed with a` greater depth of tread, a greater width of tread, and a smaller amount of resilient substance than used in conventional shoes designed for the same condi-tions in accordance with the prior art teachings.

Another object of .this invention is the provision of a `track shoe having a resilient'tread wherein the tread is The specific nature of the invention as well as other objectsl and advantages thereof will clearly appear from a description o f a preferred embodiment as shown in the accompanying drawing in which:l

uniformly vstressed to avoid disintegration thereof. f

is an integral met! -arcuate members each other at adjacent endsby arcuate portions I-5-and I'B, respectively, struck on similar predetermined radii, to form a transversely elongated tubular element indicated in its entirety by the character I1. Preferably the Itubular element i1 c element formed from seamless steel tubing. At either of the ends of element -|1 an arcuate member -IB coextensive inwidth with the element l1 and struck on a radius corresponding to the radii' of arcuate portions I5 and i6 -is inserted therewithin with the concavities ofthe members confronting the concavities of portions i5 and it, respectively, to form generally cylindrical bearings I'S and Ztl for the bushings of the track shoe interconnecting links, The

' I8 may be secured within element l-1 in any desir-able manner; but, as herein shown are retained in position against inward displacement by inwardly extending ridges 2 I deformed from members I3 and M into abutting engagement with the convex sides of the-memtheir longitudinal edges. As'will be obvious from inspectioroutward displacement of members 'I8 will be prevented` by the link pin i by characters bushings which are inserted inthe bearings -Ii and 2l.

The insert Il thus formed is suitably embedded in transversely enclosed relation by the resilient tubular block I2 of any desirable resilient substance, such as rubber by molding or in other suitable manner and where the members I9 are retained in position by ridges 2I as in Fig. 1 the ridges will also serve to eiect a substantial bond betweenthe insert II and block i12.

By forming a composite track shoe in accordance with the above disclosure it will be noted that the tread 22 of the block may be extended to the lateral edges of the insert I'I which makes it possible to employ the overall width of' the track shoe as a tread surface and thereby materially increase the widthof the tread of a track shoe of given overall width inasmuch as no part of the overall width is occupied by side links for interconnecting the bushing housings or bearings I9 and 20. This construction will therefore correspondingly decrease the unit pressure on the track shoe and increase its life. Likewise the life ot the shoe in use is increased as the effective depth of the tread 22 by this construction is l the depth of the block I2 on the tread face, in

that the elimination of side links for intercon necting the bearings I9 and 20 eliminates the protrusion of any metallic portions into the tread depth of the block I 2 beyond the outer surface of portion I4. which would limit the depth of rubber in the tread of the block I2 effective iorvuse to a depth corresponding with the outer surface of any such protrusions. Furthermore by a construction such as shown in Fig. 1, a relatively. large unobstructed interior space 2|' open at both ends is provided which permits unimpeded radiation from the insert II of the heat developed in the track for the purpose of preventing deterioration of the shoe from overheating.

In Fig. 3 a slight modification of the insert- II as shown in Fig. 2 is disclosed. As modified in this case the insert I I is provided at spacedinter- The modification in Fig. 5 is quite similar to the structure of Fig. 4. The bearing 25 is formed from a tubular element of circular -section as in the case of the structure of Fig. 4 and likewise transversely extending reinforcing webs 28 -are provided but in this form of the invention the webs and bearings 25' are secured within element 24 by the welding 29. I! desired the bearing 2l may additionally be welded to element 2|*l as by the spot welds Il.

The modified reinforcing insert shown in Fig. 6 Y

comprises a transversely elongated tubular reinforcing element 3| having its opposed side portions 32 andy Il inwardly deformed in parallel spaced relation as shown and provided with spaced integral transverse reinforcing webs or vals with reinforcing struts or plates 22.extended between the interior surfaces of portions I 3 and Il intermediate the bearings I9 and 20 to reenforce the insert against buckling upon impact of the track shoe with any uneven surface tending to throw the entire 'load on the shoe between bearings I9 and 20. While the reinforcements 22 may take any suitable form they are herein shown as comprising plates 22' perforated at 22 to permit unobstructed radiation of heat and escape of mud.

Fig. 4 shows a modication of the track shoe comprising a transversely elongated tubular element 2l similar tothe element II of insert II. In this case, however, the link pin bearing 29 is formed from a tubular element o f generally circular section inserted within the element 24 in snug engagementwith the arcuate portion 2i and retained in place'by a continuous or series of spaced interlocking indents 21 formed in the elements 2t and 25. Although only one bearing 2l of the track shoe is shown it will of course be obvious that the complete trackshoe will include a second bearing symmetrically disposed as in the case of Fig. 2. If desired longitudinally spaced transversely extending webs 2l maybe Ainterposed between link pin bearings to reinings 25.

ribs 2| formed during the deforming of parts 32 and Il. The link pin bearings may be formed in this insert as in any of the hereinbefore described methods.

Having now particularly described the invention, what I claim and desire to secure by U. S. Letters Patent is:

1. A composite track shoe including an uni-i` tary metallic insert coextensive in width with the widthof the track comprised of two opposed, spaced substantially parallel, and rectangular portions joined at their adJacent transverse ends by arcuate portions, and a resilient tubular block coextensive in longitudinal dimension with said insert secured to and transversely enclosing the same. said track shoe being open across both of its longitudinal ends whereby thorough ventilation of the shoe is provided.

2. A composite track shoe including an unitary metallic insert coextensive in width with the width of the track comprised of two opposed, spaced substantially parallel and rectangular portions Joined at their adjacent transverse ends by arcuate portions, bearings formed within said insert at`its opposed transverse ends adapted to receive link pins for interconnecting a plurality of the shoes into an endless track, and a resilient tubular block coextensive in longitudinal dimension with said insert secured to and transverse# ly enclosing the same, said track shoe being open across both of its longitudinal ends; whereby through ventilation of the shoe is provided.

3. A composite track shoe including an unitary metallic insert coextensive in width with the width of the track comprised of. two opposed, spaced substantially parallel and rectangular portions joined at their adjacent transverse ends -by arcuate portions. arcuate bearing forming members secured within the insert in parallelism with said arcuate portions, respectively, to provide bearings adapted to receive link pins for interconnecting a plurality of the shoes into an endless track. and a resilient tubular block coextensive in longitudinal dimension with said insert secured to and transversely enclosing the same. said track shoe being open across both of its longitudinal ends; whereby through ventilation of the shoe is provided.

4. The structure of claim 3 wherein the means for securing said arcuate bearing forming members within the insert comprises detents indented from the rectangular portions into engagement with the longitudinal edges of said arcu- :it bearing forming members on their convex 5. The structure of claim 3 wherein reinforce# ments spaced longitudinally of the track shoe are extended between opposed rectangular por- 2,242,222 3 tions intermediate said longitudinal bearing l 8. The structure oi claim 6 wherein spaced forming arcuate members. longitudinally of said shoe webs are interposed 6. A composite track shoe including an unibetween said tubular elements in engaging retary metallic insert coextensivein width with the lation therewith. o

width of the track comprised of two opposed 5 9. In a track shoe an unitary insert coe'xtenspaced substantially parallel and rectangular sive in width with the width of the track comportions joined at their adjacent transverse ends prising a transversely elongated tubular element by arcuate portions, tubular elements of substanprovided with inwardly depressedparallel sides tially circular cross section disposed within and joined at adjacent opposed ends by arcuate porsecured to the insertin engagement with said ar- 10 tions and longitudinally spaced webs lying wholly cuate portions, respectively, to provide bearings within said`depressions and transversely extendadapted to receive link pins for interconnecting ing between said arcuate portions.

a plurality of the shoes into an endless track, and 10. A track shoe comprising a transversely a resilient tubular block coextensive in longituelongated tubular unitary insert ccextensive in dinal dimension with said insert secured to and 15 width with the width of the track having paraltransversely enclosing the same, said track shoe lel sides joined at opposed adjacent ends by arbeing open across both of its longitudinal ends; cuate portions and a resilient tubular block cowhereby through ventilation og the shoe is proextensive in longitudinal dimension with said invided. L Y. sert secured to and transversely enclosingthe 7. The structure of claim 6y wherein said tu- 20 same, said track' shoe being open across both of bular elements of substantially circular cross itslongltudinal ends; whereby through ventilasection are secured in position by cooperating intion of the shoe is provided. Adents formed in the insert and tubular elements. Y VIRGIL O. BEEpE. 

